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Fifth letter containing suspicious substance found at UC Irvine

Another envelope containing a suspicious substance was discovered at UC Irvine today, the fifth such letter found on campus this week.

In the latest case, an assistant to an associate professor of arts felt something granular in an envelope she was about to open and notified authorities.

Like all the suspicious envelopes discovered since Monday at UC Irvine, it had an Idaho postmark. Campus officials said they have taken steps to scrutinize incoming mail and sent out warnings to not open unexpected letters from Idaho.

Tests on the substances in the previous letters, which included the message “black death,” found them to be harmless. Nevertheless, today’s incident was handled like the others — by an Orange County Fire Authority hazardous materials team.

All five letters were sent to faculty members in a variety of departments. Aside from that, a pattern as to who is being targeted has yet to emerge, said university spokeswoman Cathy Lawhon.

“At first the only pattern was that they were all women,” she said. “This latest one” — sent to a male associate professor of arts — “breaks that pattern.”